This relates to generation of sequential color illumination in solid state laser projection systems and the like.
An example solid state projector using blue lasers and a phosphor color wheel as an illumination source and a spatial light modulator for modulation of the emitted light is described in Patent Application Pub. No. US 2013/0242534 A1, published Sep. 19, 2013, entitled “Projector Light Source and System, Including Configuration for Display of 3D Images,” the entirety of which is incorporated herein by reference. Such system utilizes blue lasers as a direct source of blue color light and utilizes the blue lasers as an indirect source of other color light by energizing other color light producing phosphors with the blue color light from the blue lasers. Efficient blue lasers available for use in such solid state projectors are, however, often not of suitable wavelength to create a pleasing blue color when observed displayed on a screen or other display surface.
A typical phosphor color wheel as used in the described solid state projector has arcuate segments coated with different color emitting phosphors annularly positioned at circumferentially angularly spaced locations about a circular wheel. An example color wheel having circular tracks or bands of different color emitting phosphors spaced at different concentric radially spaced locations is described in Patent Application Pub. No. US 2011/0211333 A1, published Sep. 1, 2011, entitled “Wavelength Conversion,” the entirety of which is incorporated herein by reference.
The use of cyan phosphor in combination with blue laser light to form a more pleasing blue in a sequential color illumination system that utilizes a blue light wraparound path is described in Application No. 61/752,294 filed Jan. 14, 2013, entitled “Method of Utilizing a Cyan Phosphor to Color Correct a Laser Illuminated Projection System,” the entirety of which is incorporated herein by reference.